CVE-2026-54463: faye websocket-driver

Vulnerability summary

CVE-2026-54463 is a high (CVSS 7.5) vulnerability in faye websocket-driver. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 40.9% of scored vulnerabilities.

Timeline

1. 17-07-2026
   PublishedVulnerability first disclosed.
2. 20-07-2026
   Last modifiedVulnerability information updated.

Description

websocket-driver is a WebSocket protocol handler with pluggable I/O. Prior to 0.8.1, draft versions of the WebSocket protocol in websocket-driver include a length header that allows an arbitrarily large integer to be encoded as bytes with the high bit set, and a server or client can send an indefinite sequence of 0x80 or higher bytes that the peer parses into an ever-growing Ruby integer. This can make a WebSocket connection consume an unbounded amount of memory and lead to the host process running out of memory. This issue is fixed in version 0.8.1.

• CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.